#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <pthread.h>

#define NUM_THREADS 6

void * thread_function(void * arg);

int main()
{
  int res;
  pthread_t a_thread[NUM_THREADS];
  void * thread_result;
  int lots_of_threads;

  for (lots_of_threads = 0; lots_of_threads < NUM_THREADS; lots_of_threads++) {
    res = pthread_create(&(a_thread[lots_of_threads]), NULL, thread_function, (void *) &lots_of_threads);
    if (res == 0) 
      printf("Picked up a thread\n");
    else
      perror("pthread_join failed");
  }

  printf("All done\n");
  exit(EXIT_SUCCESS);
}

void * thread_function(void * arg) {
  int my_number = * (int *) arg;
  int rand_num;

  printf("thread_function is running. Argument was %d\n", my_number);
  rand_num = 1 + (int) (9.0 * rand() / (RAND_MAX + 1.0));
  sleep(rand_num);
  printf("Bye from %d\n", my_number);
  pthread_exit(NULL);
}
